{
  "cveId": "CVE-2026-67240",
  "url": "https://patchblox.com/security/cve/CVE-2026-67240",
  "summary": "CVE-2026-67240 is fixed in rabbitmq-server on 1 platform by DEBIAN-CVE-2026-67240 (version 4.3.2-1), released September 25, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "rabbitmq-server: RabbitMQ is a messaging and streaming broker",
  "description": "RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, pattern_to_regex maps % -\u003E .*? and _ -\u003E ., then compiles ^...$ with only [unicode]; re:run is called with only [{capture, none}] - no explicit match_limit. A pattern like %_%_..._%X becomes ^.*?..*?.....*?.X$ with overlapping lazy quantifiers. The whole-expression cap is ?MAX_EXPRESSION_LENGTH=4096 chars / ?MAX_TOKENS=200; a LIKE string literal is one token, so ~2000 %_ pairs fit. SQL filters are accepted unconditionally at rabbit_amqp_session.erl:3264 (no feature flag). Evaluated per-message at rabbit_stream_queue.erl:1439. OTP\u0027s default 10M match_limit caps each match at ~100-200 ms (not seconds), and the re NIF yields to the scheduler. An authenticated AMQP 1.0 consumer with read\u002Bwrite on a stream queue can cause ~100-200 ms of CPU per delivered message via a crafted LIKE filter, multiplied across thousands of messages and parallel sessions - a substantial backtracking-driven CPU amplification. Preconditions include AMQP 1.0 with stream queues in use Attacker can attach a receiver with a filter (read permission) and publish messages with long property values (write permission). This issue is fixed in versions 4.2.7 and 4.3.1.",
  "published": "2026-09-23T21:17:01Z",
  "severity": "medium",
  "cvss": 6.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.00372,
  "epssPercentile": 0.31319,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "rabbitmq-server",
      "release": "Debian 14",
      "fixedVersion": "4.3.2-1",
      "fix": "DEBIAN-CVE-2026-67240",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-67240",
      "released": "2026-09-25T19:41:43Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T13:31:49Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}